It's a sad fact that most guys who think they have good abs are only partially correct. More often than not, the upper half of their rectus abdominis -- the wall of muscle that makes up the coveted eight-pack -- is fairly well developed while the lower half is languishing. That is to say, their lower abs may be "flat" but they're definitely not "fantastic." This is almost always due to years of abs training that focused on crunch-based movements that target the upper abs. If you want good, top-to-bottom abdominal aesthetics, it's time to alter your exercise selection to suit that goal with exercises that emphasize that area by bringing your hips toward your rib cage, rather than the other way around.

"Your lower abs consist mainly of your rectus abdominis and transverse abdominis," says Matt Choate, NASM-CPT, a personal trainer based in Long Beach (Calif.). "While any abdominal exercise engagesall of your stomachmuscles, these exercises tend to focus more on the lower half."

Choate recommends incorporating these three exercises, for starters, into your usual routine, or using the program provided below to really blast your lower abs into submission.

Reverse Crunch

Lie face up on the ground with your hands extended at your sides, feet up and thighs perpendicular to the ground. Slowly bring your knees toward your chest, lifting your hips and glutes off the ground, and try to maintain the bend in your knees throughout the movement. Return under control.

Grasp an overhead bar with pronated (palms forward) grip. Wrap your thumbs around the bar. Keeping your legs together, allow them to hang straight down directly beneath you. Keeping your legs straight, raise them up directly in front of you until your legs are just above parallel to the floor. Hold as long as possible, then slowly lower them back to the start and repeat.

"This exercise works the whole spectrum of your upper and lower abs, along with your obliques," says Choate. "The more difficult version is to put your legs out straight, but if this is too hard you can always bend your legs and then raise them to your sternum."

Incline Reverse Crunch

Lie face-up on an incline bench with your hands holding the bench overhead. Begin with your legs bent 90 degrees at the hips and knees. Contract your abs to slowly raise your legs by lifting your glutes up while keeping your knees bent and bringing your knees toward your head. Slowly lower your legs back to the start position and repeat for reps.

This more advanced version of the reverse crunch allows you to better isolate your lower abs with greater resistance. Concentrate on elevating your glutes, rather than simply bringing your knees to your chest.

"Perform each of these exercise slow and with control," says Choate. "Always rememberto do quality reps, and focus on using the correct muscles for each exercise.Do not cheat by using momentum to get you through."

Perform this routine in straight-sets fashion, completing all sets for one exercise before moving on to another. Rest no longer than 60 seconds between sets. Perform this routine once per week in addition to your usual abs routine.